Abstract

The Lower Cretaceous echinoids from the carbonate rocks of the El Way Formation, deposited in the Coloso Basin, northern Chile, are described. Six species were identified: four of them not previously reported for the El Way Formation, Temnocidaris (Stereocidaris) malum (Gras), Tetragramma tenerum Smith and Rader, Leptosalenia prestensis (Desor) and Leptosalenia texana (Credner); an endemic species, Pliotoxaster andinum sp. nov.; and another species already mentioned in previous studies, Phymosoma mollense (Paulcke). In addition, other three different species are described and left in open nomenclature (Tetragramma sp., Phymosoma sp. and Saleniidae indet.) and the species Hemiaster wayensis (Larraín) is reassigned to the genus Pliotoxaster Fortau. The fossil echinoids collected in the Coloso Basin show different temporal distributions, all between the late Barremian and early Aptian.